So I'm not sure if this is normal or not but on my 8 month old Riley his left side rib cage pertrudes out way farther than the right side. I actually just noticed it today. I mean, I have always noticed his rib cage. Okay, not the rib cage but the natural curves. Like if you took a picture of it from above him you would notice. Maybe I am just paranoid because I really sat and looked at it today. I ran my hands over it and pushed on it and stuff and it didn't bother him. I am going to post a picture from the top later. My batter in my camera is dead so I've got to get some new ones. By the way, he is not underweight or anything. He's 70 pounds if not bigger, he's not fat though. I guess if I had to describe the way it looks it's as if it looks pregnant on one side. Not hugely but it's noticeable if you look.